Prevalence of and risk factors for gallbladder polyps detected by ultrasonography among healthy Chinese: analysis of 34 669 cases

Diagnosis and treatment of gallbladder polypoid lesions: Current practices and future prospects

ABSTRACT

Gallbladder polypoid lesions (GPLs) refer to any elevated lesion of the mucosal surface of the gallbladder wall, and the prevalence is estimated to be between 0.9% and 12.1%. GPLs include benign polyps and malignant polyps. Benign polyps are further classified as non-neoplastic polyps and neoplastic polyps. Cholesterol polyps are the most common benign polyps and adenocarcinoma is the main type of malignant polyp. Hepatitis B virus infection, liver function abnormalities, dyslipidemia, and obesity are the main risk factors for GPLs. Studies of biological mechanisms have focused on malignant gallbladder polyps, the development of which is regulated by hormone levels in vivo , gut microbiota, inflammation, oxidative stress, Salmonella typhimurium , and related molecules. Diagnostic modalities include chemical examination and imaging examination, with imaging examination currently being the mainstay. Treatment of patients with GPLs is based on the presence or absence of symptoms, age, size of the polyps, tendency of the polyp to increase, and risk factors for symptomatic malignancy to determine whether surgery should be performed.

Impact of hepatitis B virus infection on the risk of gallbladder polyps: a cohort study

BACKGROUND/AIMS

We aimed to determine whether hepatitis B virus (HBV) or hepatitis C virus (HCV) infection remains an important risk factor for gallbladder polyps (GBPs) in the current context of reduced prevalence of these infections.

METHODS

The cohort included 392,913 asymptomatic adults who underwent abdominal ultrasonography (US).

RESULTS

The prevalence of GBP sized ≥ 5 mm, ≥ 10 mm, and overall (< 5, 5-9 and ≥ 10 mm) was 2.9%, 0.1%, and 12.8%, respectively. The prevalence of hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb), and hepatitis C antibody (anti-HCV) positivity was 3.2%, 26.7%, and 0.1%, respectively. The GBP risk was significantly increased in HBsAg-positive individuals, with an adjusted odds ratio of 1.66 (95% confidence interval, 1.49-1.85) for GBP ≥ 5 mm, 2.39 (1.53-3.75) for GBP ≥ 10 mm, and 1.49 (1.41-1.59) for overall, whereas there was no significant association between anti-HCV positivity and GBP risk. The GBP risk did not increase significantly in individuals who tested negative for HBsAg but positive for HBcAb.

CONCLUSION

The presence of HBsAg may be an independent risk factor for GBP development in the current context of a indecreasing prevalence of HBsAg positivity. A more comprehensive evaluation of GBP during abdominal US surveillance of HBsAg-positive individuals may be necessary.

Small Intestinal Bacterial Overgrowth in Patients with Gallbladder Polyps: A Cross-Sectional Study

Purpose

There is probably a high prevalence of small intestinal bacterial overgrowth (SIBO) in patients with gallbladder polyps (GBPs). To date, no study has evaluated the occurrence of SIBO in patients with GBPs. The aim of this study was to investigate the prevalence of SIBO in patients with GBPs and explore the possible association between these two conditions.

Patients and Methods

The hydrogen-methane breath test was used to diagnose SIBO, and patients were divided into GBPs and control groups based on whether GBPs were found under ultrasound. Clinical and paraclinical factors were compared between the two groups.

Results

A total of 297 subjects were included in this study. The prevalence of SIBO was significantly higher in the GBPs group than in the control group (50.0% vs.30.8%, p<0.01). Multivariate logistic regression analysis showed that male (OR=2.26, 95% CI=1.12-4.57, p=0.023), SIBO (OR=3.21, 95% CI=1.69-6.11, p<0.001), fatty liver (OR=2.91, 95% CI= 1.50-5.64, p=0.002) and BMI (OR=1.13, 95% CI=1.01-1.26, p=0.035) were independently associated with GBPs. And by subgroup analysis, we found that the association between SIBO and GBPs was stronger in females than in males (p for interaction< 0.001). In addition, SIBO (OR=5.11, 95% CI=1.42-18.36, p=0.012) and fasting glucose (OR=3.04, 95% CI=1.27-7.28, p=0.013) were found to be associated with solitary polyps.

Conclusion

SIBO was highly prevalent in patients with GBPs, and this association seemed to be stronger among females.

Combining polyp diameter and polyp-to-bile ratio by dynamic contrast-enhanced CT scanning can improve the diagnostic specificity of gallbladder neoplastic polyps

OBJECTIVE

This study aimed to distinguish between cholesterol and neoplastic gallbladder polyps using dynamic contrast-enhanced CT.

METHODS

The dataset retrospectively comprised 222 cases, including 106 cases of cholesterol polyps and 116 cases of neoplastic polyps (59 adenoma and 57 adenocarcinoma). The perception and Hounsfield units of the polyps and gallbladder bile were assessed by contrast-enhanced CT, and the polyp-to-bile ratio (PBR) was calculated. Receiver operating characteristic (ROC) curves and area under the curve analyses were used to assess the diagnostic value of the diameter and PBR for neoplastic polyps.

RESULTS

The diameter of cholesterol polyps was significantly smaller than that of neoplastic polyps. The proportion of perceived cholesterol polyps in the plain and arterial phases of CT were significantly lower than those of neoplastic polyps (p < .001). On the contrary, the CT values of gallbladder bile of cholesterol polyps were always significantly higher than those of neoplastic polyps (p < .001). The median PBR values of cholesterol polyps were significantly lower than those of neoplastic polyps (p ≤ .001). ROC analysis showed that diameter and a plain phase PRB had better diagnostic value for neoplastic polyps. Polyp diameter ≥ 11.95 mm and the plain phase PBR ≥1.48 were the optimal cut-off values for diagnosis of neoplastic polyps. Combining a diameter ≥ 12 mm and a PBR in the plain phase ≥1.48 further improved neoplastic polyp diagnostic specificity and positive likelihood ratio (10.453).

CONCLUSIONS

Polyp-to-bile ratio in contrast-enhanced CT scanning is a new and convenient index for identifying cholesterol and neoplastic gallbladder polyps.

Incidental Findings of Gallbladder and Bile Ducts-Management Strategies: General Aspects, Gallbladder Polyps and Gallbladder Wall Thickening-A World Federation of Ultrasound in Medicine and Biology (WFUMB) Position Paper

The World Federation of Ultrasound in Medicine and Biology (WFUMB) is addressing the issue of incidental findings with a series of position papers to give advice on characterization and management. The biliary system (gallbladder and biliary tree) is the third most frequent site for incidental findings. This first part of the position paper on incidental findings of the biliary system is related to general aspects, gallbladder polyps and other incidental findings of the gallbladder wall. Available evidence on prevalence, diagnostic work-up, malignancy risk, follow-up and treatment is summarized with a special focus on ultrasound techniques. Multiparametric ultrasound features of gallbladder polyps and other incidentally detected gallbladder wall pathologies are described, and their inclusion in assessment of malignancy risk and decision- making on further management is suggested.

Value of Conventional Ultrasound-based Scoring System in Distinguishing Adenomatous Polyps From Cholesterol Polyps

BACKGROUND AND AIM

Ultrasound has increased the detection of gallbladder polyps, but it has limitations in evaluating the nature of gallbladder polyps, especially the maximum size of 1.0 to 1.5 cm. We assessed the value of ultrasound scoring system based on independent predictive parameters in distinguishing adenomatous polyps from cholesterol polyps with the maximum size of 1.0 to 1.5 cm.

MATERIALS AND METHODS

We enrolled 163 patients with gallbladder polyps (1.0 to 1.5 cm) who underwent ultrasonography and cholecystectomy. Ultrasound image characteristics were compared between cholesterol polyps and adenomatous polyps in the training cohort from April 2018 to January 2020. An ultrasound scoring system was constructed in the training cohort, and its diagnostic performance was evaluated in the validation cohort from February 2020 to February 2021.

RESULTS

Maximum size, height/width ratio, stone or sludge, vascularity, and hyperechoic spot were significantly different between cholesterol polyps and adenomatous polyps in the training cohort ( P <0.05). The independent predictive parameters for adenomatous polyps were lower height/width ratio, presence of vascularity and absence of hyperechoic spot. The total score was as follows: (height/width ratio, <0.9=4, ≥0.9=0) + (vascularity, present=3, absent=0) + (hyperechoic spot, absent=2, present=0). The sensitivity, specificity and accuracy of ultrasound scoring system ≥5 for diagnosis of adenomatous polyps in the validation cohort were 73.33%, 80.49%, and 78.57%, respectively.

CONCLUSIONS

The ultrasound scoring system aids in distinguishing adenomatous polyps from cholesterol polyps, and effectively decreasing unnecessary cholecystectomy.

Risk factors for gallbladder polyps observed through second-look abdominal sonography in patients with fatty liver disease

FLD, older age group, and alcohol consumption are major risk factors of GBP formation in Taiwanese population. The presence of GBPs might be revealed in second-look examinations of abdominal sonographies.

Follow-up of gallbladder polyps in a high-risk population of gallbladder cancer: a cohort study and multivariate survival competing risk analysis

BACKGROUND

The risk of neoplasia in gallbladder polyps seems to be low, but the evidence from populations at high-risk of gallbladder cancer is limited. We aimed to estimate the risk and to identify the factors associated with neoplastic polyps in a high-risk Hispanic population.

METHODS

A retrospective cohort was recruited between January 2010 and December 2019 at a Chilean university center. Multivariate survival analyses were conducted. Fine-Gray models were fitted to account for competing risks. Covariate adjustment was conducted using propensity scores. The main outcome was the development of gallbladder adenomas or adenocarcinoma.

RESULTS

Overall, 748 patients were included, 59.6% underwent cholecystectomy. The median follow-up of patients not subjected to cholecystectomy was 54.7 months (12-128.6 months). Seventeen patients (2.27%) developed the outcome. After adjustment by age, sex, intralesional blood flow, lithiasis and gallbladder wall thickening, only polyp size (≥10 mm, adjusted-HR: 15.01, 95%CI: 5.4-48.2) and number of polyps (≥3 polyps, adjusted-HR: 0.11, 95%CI: 0.01-0.55) were associated with neoplasia.

CONCLUSION

In a Hispanic population at high-risk for gallbladder cancer, gallbladder polyps seem to have a low risk of neoplasia. Polyp size was the main risk factor, while having multiple polyps was associated with an underlying benign condition.

[Differential diagnosis of gallbladder polypoid lesions by micro-flow imaging]

OBJECTIVE

To explore the value of micro-flow imaging (MFI) in evaluating blood flow characteristics and differential diagnosis of gallbladder polypoid lesions.

METHODS

We retrospectively analyzed the clinical data and ultrasound images of 73 patients with gallbladder polypoid lesions, including 24 patients with pathologically confirmed neoplastic polyps (n=24) and 49 with non-neoplastic polyps (n=49). All the patients underwent conventional ultrasound, MFI and contrast enhanced ultrasound (CEUS) before cholecystectomy. The blood flow characteristics of the lesions in color Doppler flow imaging (CDFI) and MFI were compared, and the consistency of the findings by these two modalities with those of CEUS were evaluated by weighted Kappa consistency test. The diagnostic performance of MFI for gallbladder polypoid lesions was assessed.

RESULTS

There were significant differences between MFI and CDFI in the evaluation of blood flow characteristics of gallbladder polypoid lesions (χ²=37.684, P < 0.001). MFI showed better performance than CDFI in displaying the blood flow characteristics of the polyps. The consistency in the findings was 0.118 between CDFI and CEUS and 0.816 between MFI and CEUS. The sensitivity, specificity and accuracy of MFI in distinguishing neoplastic polyps from non-neoplastic polyps were 75.00%, 93.88% and 87.67%, respectively.

CONCLUSION

MFI has a good consistency with CEUS in displaying the blood flow characteristics of gallbladder polypoid lesions and can accurately distinguish neoplastic polyps from non-neoplastic polyps, thus providing new ultrasound diagnostic evidence to support clinical decisions on optimal treatments of gallbladder polypoid lesions.

Gallbladder-preserving polypectomy for gallbladder polyp by embryonic-natural orifice transumbilical endoscopic surgery with a gastric endoscopy

Background and aims

Cholecystectomy is performed for most gallbladder polyps (GPs). However, cholecystectomy results concerning complications in some patients. For benign GPs, adoption of gallbladder-preserving surgery is worth to recommend. We describe our experiences performing gallbladder-preserving polypectomy for GPs by embryonic-natural orifice transumbilical endoscopic surgery (E-NOTES) with a gastric endoscopy.

Methods

This is a retrospective study of patients with GPs who underwent gallbladder-preserving polypectomy by E-NOTES with a gastric endoscopy from April 2018 to September 2019 in our hospital. The operative time, intraoperative hemorrhage, intraoperative and postoperative complications, gallbladder emptying function were obtained and analyzed.

Results

The procedure was performed successfully in all 12 patients with 5 cases of single polyp and 7 cases of multiple polyps. The range of GPs size was 2 mm to 15 mm. The mean operation time was (95.33 ± 23.08) minutes (55–135 min). There were no adverse events including heavy bleeding, mortality and conversion to open surgery during operation. All patients were discharged in 4–5 days after surgery without postoperative complications such as delayed bleeding, fever, peritonitis, intra-abdominal abscess and abdominal wall incisional hernia. All patients were followed up at 1, 3, 6, and 12 months postoperation who had almost no visible incision on the umbilical region, no recurrent GPs. The gallbladder emptying function decreased one month after surgery, and gradually improved 3, 6 and 12 months after surgery.

Conclusion

E-NOTES gallbladder-preserving polypectomy is a safe and effective option for patients with GPs and is close to scar-free surgery which can be performed in routine clinical practice.

Development and Validation of a Preoperative Nomogram for Predicting Benign and Malignant Gallbladder Polypoid Lesions

Purpose

The purpose of this study was to develop and validate a preoperative nomogram of differentiating benign and malignant gallbladder polypoid lesions (GPs) combining clinical and radiomics features.

Methods

The clinical and imaging data of 195 GPs patients which were confirmed by pathology from April 2014 to May 2021 were reviewed. All patients were randomly divided into the training and testing cohorts. Radiomics features based on 3 sequences of contrast-enhanced computed tomography were extracted by the Pyradiomics package in python, and the nomogram further combined with clinical parameters was established by multiple logistic regression. The performance of the nomogram was evaluated by discrimination and calibration.

Results

Among 195 GPs patients, 132 patients were pathologically benign, and 63 patients were malignant. To differentiate benign and malignant GPs, the combined model achieved an area under the curve (AUC) of 0.950 as compared to the radiomics model and clinical model with AUC of 0.929 and 0.925 in the training cohort, respectively. Further validation showed that the combined model contributes to better sensitivity and specificity in the training and testing cohorts by the same cutoff value, although the clinical model had an AUC of 0.943, which was higher than 0.942 of the combined model in the testing cohort.

Conclusion

This study develops a nomogram based on the clinical and radiomics features for the highly effective differentiation and prediction of benign and malignant GPs before surgery.

The Role of Endoscopic Ultrasound in the Diagnosis of Gallbladder Lesions

Gallbladder (GB) diseases represent various lesions including gallstones, cholesterol polyps, adenomyomatosis, and GB carcinoma. This review aims to summarize the role of endoscopic ultrasound (EUS) in the diagnosis of GB lesions. EUS provides high-resolution images that can improve the diagnosis of GB polypoid lesions, GB wall thickness, and GB carcinoma staging. Contrast-enhancing agents may be useful for the differential diagnosis of GB lesions, but the evidence of their effectiveness is still limited. Thus, further studies are required in this area to establish its usefulness. EUS combined with fine-needle aspiration has played an increasing role in providing a histological diagnosis of GB tumors in addition to GB wall thickness.

Are there modifiable risk factors affecting the prevalence of gallbladder polyps or those 5 mm or larger? A retrospective cross-sectional study

Gallbladder polyps (GBPs), especially GBPs ≥5 mm in diameter, are clinically important because they can progress to gallbladder cancer. The known modifiable risk factors for GBP are obesity, metabolic syndrome, and dyslipidemia; however, there is limited evidence regarding specific modifiable risk factors for GBPs ≥5 mm in diameter. Therefore, this study is aimed to investigate the existence of modifiable risk factors affecting the prevalence of GBPs and GBPs ≥5 mm in diameter in a Korean population.A total of 10,119 subjects who visited a single health-screening center at Jeju National University Hospital between January 2009 and December 2019 was included in this study. Binary logistic analyses were performed to identify risk factors affecting the prevalence of GBPs and GBPs ≥5 mm in diameter.The overall prevalence of GBPs and GBPs ≥5 mm in diameter were 9.0% and 4.1%, respectively. Multivariable analysis identified male gender as an independent risk factor affecting the prevalence of GBPs. Moreover, multivariable analysis revealed age and high-density lipoprotein cholesterol levels as independent risk factors for GBPs ≥5 mm in diameter.This study showed that gender was a risk factor affecting the prevalence of GBPs and that age and high-density lipoprotein-cholesterol levels were risk factors for the presence of GBPs ≥5 mm in diameter. High-density lipoprotein cholesterol levels could be a modifiable risk factor affecting the prevalence of large-diameter GBPs.

Schistosoma gallbladder polyp masquerading as a neoplasm: Rare case report and literature review

Schistosomiasis affecting the gastrointestinal tract is common in tropical and subtropical areas but associated polyps presenting as gallbladder pathology are rare clinical entities necessitating high clinical suspicion.

Safety of ambulatory laparoscopic cholecystectomy in the elderly

BACKGROUND

This study aims to retrospectively analyse the safety of ambulatory laparoscopic cholecystectomy (ALC) and identify risk factors for delayed discharge after ALC in the elderly.

METHODS

Consecutive patients who were scheduled to undergo ALC were assigned to the elderly group (age ≥ 65 years) or the non-elderly group. The primary outcome was postoperative discharge within 24 h (D24). Secondary outcomes were perioperative mortality, reasons for delayed discharge (psychosocial reasons (DP), complications (DC), drainage (DD) and conversion to open surgery (DCO)), intraoperative data and readmission within 30 days after discharge (readmission). Differences were statistically significant when P < 0.05.

RESULTS

There were 7657 patients assigned to the elderly group (n = 1143) or the non-elderly group (n = 6514). The differences between elderly patients and non-elderly patients in the operation time (51.0 (37.0-70.0) versus 50.0 (35.0-65.0) min), blood loss (10.0 (5.0-10.0) versus 5.0 (5.0-10.0) mL), D24 (75.5% versus 81.7%) and DD (7.8% versus 3.2%) were statistically significant (P < 0.05, respectively). The differences between elderly patients and non-elderly patients in DP (8.2% versus 6.7%), DC (7.8% versus 7.9%), DCO (0.7% versus 0.5%) and readmission (0.5% versus 0.4%) were not statistically significant (P > 0.05, respectively). Independent risk factors for delayed discharge after ALC in the elderly were male sex, octogenarian status, prolonged operation time, arrhythmia, type 2 diabetes mellitus, a previous operation in the upper abdomen, acute inflammation of gallbladder and a gallbladder wall thicker than 3 mm (P < 0.05, respectively).

CONCLUSION

ALC in the elderly is feasible and safe.

Synchronous gallbladder metastasis of renal cell carcinoma presenting as a gallbladder polyp: A case report

RATIONALE

Gallbladder polyps are common in the general population, but gallbladder metastasis of renal cell carcinoma (RCC) is very rare. In a patient with RCC diagnosed with a small gallbladder polyp that does not meet the traditional size criteria, the surgeon faces a dilemma of whether cholecystectomy should be performed given the possibility of metastasis.

PATIENT CONCERNS

A 55-year-old man who had received a left nephrectomy for RCC presented with a gallbladder polyp that was noted at the time of the nephrectomy. Imaging showed the maximum diameter of the polyp had increased from 5 mm to 24 mm in the 40 months after the initial diagnosis.

DIAGNOSIS

Pathological and immunohistology findings confirmed the gallbladder polyp as a metastasis of clear-cell RCC.

INTERVENTIONS

: We performed a laparoscopic cholecystectomy.

OUTCOMES

Even though the synchronous solitary gallbladder metastasis was left untreated and a cholecystectomy was not performed over the 40 months, no metastasis occurred in other sites. The patient is free from disease 10 months after the cholecystectomy.

LESSONS

Solitary gallbladder metastasis of RCC may have more favorable outcomes than typical metastases. Although gallbladder metastasis of RCC occur rarely, it can occur, and any changes in gallbladder polyps in RCC patients should be managed under a strong suspicion of metastasis.

Case of a Large Pedunculated Biliary Cholesterol Polyp With Osseous Metaplasia

Cholesterol polyps are the most common benign gallbladder polyps and are usually seen in a background of cholesterolosis. Rarely, they can harbor foci of osseous metaplasia, which is an event of uncertain clinical significance that might be confused with cholelithiasis clinically or radiologically. Herein we report the case of a 78-year-old female with a 1.8-cm pedunculated polyp arising in the gallbladder body. Histologic examination showed microscopic foci of osseous metaplasia, characterized by heterotropic bone trabeculae rimmed by osteoblasts and surrounded by osteoclast giant cells. To the best of our knowledge, this case is the third case report of a cholesterol polyp with osseous metaplasia in the English literature. We also review the relative pathogenesis, clinical and pathologic findings, and previous reports.

Fatty liver is an independent risk factor for gallbladder polyps

BACKGROUND

Gallbladder polyps (GBPs) are known to be associated with obesity and metabolic diseases. However, to date, the relationship between GBPs and abnormal body fat distribution, such as fatty liver, visceral obesity, or sarcopenia, has not yet been established.

AIM

To evaluate whether GBPs are associated with fatty liver, visceral obesity, or sarcopenia.

METHODS

We retrospectively reviewed the medical records of subjects who underwent various laboratory tests, body composition measurement with a non-invasive body composition analyzer, and abdominal ultrasonography during health checkups. A total of 1405 subjects with GBPs were compared with 2810 age- and sex-matched controls.

RESULTS

The mean age of the subjects was 46.8 ± 11.7 years, and 63.8% were male. According to multiple logistic regression analysis, the presence of fatty liver [odds ratio (OR) 1.413; 95% confidence interval (CI) 1.218-1.638; P < 0.001] was an independent risk factor for GBP, together with low levels of alanine aminotransferase (OR 0.993; 95%CI 0.989-0.996; P < 0.001). Additionally, fatty liver showed both independent (OR 1.629; 95%CI, 1.335-1.988; P < 0.001) and dose-dependent (moderate to severe fatty liver; OR 2.137; 95%CI, 1.662-2.749; P < 0.001) relationship with large GBPs (≥ 5 mm). The presence of sarcopenia and high visceral fat area were not significantly associated with GBPs.

CONCLUSION

Fatty liver was found to be closely associated with GBPs irrespective of sarcopenia and visceral obesity.

Endoscopic ultrasound-guided cholecystostomy for resection of gallbladder polyps with lumen-apposing metal stent

Laparoscopic cholecystectomy is the routine method to treat gallbladder polyps. Nowadays, endoscopic ultrasound (EUS)-guided cholecystostomy as a bridge for per-oral transmural endoscopic resection of gallbladder polyps is introduced because preservation of gallbladder is increasingly getting attention. The aim of our study was to evaluate the approach in the treatment of patients with gallbladder polyps and symptomatic gallstones.EUS-guided cholecystostomy with the placement of a lumen-apposing metal stent (LAMS) was performed for those patients with accompanying gallbladder polyps and symptomatic gallstones. Several days after the cholecystostomy with LAMS, a gastroscope was introduced into the gallbladder to remove gallbladder polyps.All patients were successfully performed with the procedures of EUS-guided cholecystoduodenostomy (n = 3) or cholecystogastrostomy (n = 1) and endoscopic resection of gallbladder polyps. One patient experienced severe peritonitis. During the follow-up at 3 months, 1 patient was performed with laparoscopic cholecystectomy because ultrasonography examination showed the reappeared gallstones. No stone recurrence was found in other patients. During the follow-up of 3 to 15 months, no polyp recurrence was found in all the patients.The approach is novel for performing EUS-guided gallbladder fistulization, which can subsequently allow procedures of per-oral transmural endoscopic resection of gallbladder polyps to avoid cholecystectomy in the patients with gallbladder polyps and gallstones. However, further studies are needed before clinical recommendation because of the complications and stone recurrence.

Gallbladder polyps: evolving approach to the diagnosis and management

Gallbladder (GB) polyp is a mucosal projection into the GB lumen. With increasing health awareness, GB polyps are frequently found using ultrasonography during health screening. The prevalence of GB polyps ranges between 1.3% and 9.5%. Most patients are asymptomatic and have benign characteristics. Of the nonneoplastic polyps, cholesterol polyps are most common, accounting for 60%-70% of lesions. However, a few polyps have malignant potential. Currently, the guidelines recommend laparoscopic cholecystectomy for polyps larger than 1 cm in diameter due to their malignan potential. The treatment algorithm can be influenced by the size, shape, and numbers of polyps, old age (>50 years), the presence of primary sclerosing cholangitis, and gallstones. This review summarizes the commonly recognized concepts on GB polyps from diagnosis to an algorithm of treatment.

Management of gallbladder polyps

A gallbladder polyp (GP) is defined as an elevation of the gallbladder mucosa that protrudes into the gallbladder lumen. Gallbladder polyps (GPs) have an estimated prevalence in adults of 0.3–12.3%. However, only 5% of polyps are considered “true” GPs that have malignant potential or are even already cancerous. The most important imaging method for diagnosis and follow-up of GPs is transabdominal ultrasound, but it fails to discriminate between true and pseudo polyps at a clinically relevant level. Although gallbladder cancer (GBC) arising from polyps is a rare event, malignancy is significantly more common among polyps from a size of 10 mm. In light of this, the consensus, which is reflected in current guidelines, is that surgery should be considered for polyps of 10 mm or greater. However, 10 mm is an arbitrary cutoff, and high-quality evidence to support this is lacking. Lowering the threshold for cholecystectomy when patients have additional risk factors for gallbladder malignancy may improve the cancer detection rate in polyps smaller than 10 mm. Nevertheless, the evidence behind this is also weak. This review shows the shortcomings in the available evidence and underlines the decision-making process regarding the surgical indication, surveillance, or both.

Analysis of risk factors for gallbladder polyp formation - A retrospective study based on serial ultrasounds

AIM

To evaluate gallbladder polyp (GBP) formation related risk factors based on serial ultrasounds (US).

METHODS

Risk factors related GBP formation were retrospectively investigated among participants, who had US reexamination and interval >180 days in 5 years. After groups were divided based on US, we compared final data and initial data in GBP new incidence group. Then compared the data in GBP new incidence group and GBP(-) group.

RESULTS

Overall 20 447 participants were recruited, including 18 243 in GBP (-) group and 2204 in GBP group. The mean diameters of polyps were 0.455 ± 0.198 mm in initial and 0.420 ± 0.180 mm in final examination. GBP new incidence group included 797 participants. Percentage of GBP new incidence participants was higher than GBP resolved (36.16% vs. 11.71%). Participants in middle age were more likely have GBP size increase or new incidence, and participants in old age (≥60 years old) were with GBP size decrease or resolved. In GBP new incidence group, participants in final US showed higher FBG, higher LDL, lower HDL, higher ALT and higher AST than initial US. Compared with GBP (-) group and, same risk factors, in addition with age, were shown in GBP new incidence group, Logistic regression analysis show that higher LDL, lower HDL and higher AST were risk factors for GBP formation.

CONCLUSION

Participants in middle age were more likely to have GBP new incidence. Higher LDL, lower HDL and higher AST were independently risk factors for GBP formation.

Role of endoscopic ultrasound for gallbladder disease

Endoscopic ultrasonography (EUS) has excellent spatial resolution and allows more detailed examination than abdominal ultrasonography (US) in terms of qualitative diagnosis of tumors and evaluation of tumor invasion depth. To understand the role of EUS in gallbladder disease, we need to understand the normal gallbladder wall structure and how to visualize it on EUS. In addition, gallbladder lesions can be classified into two broad categories: protuberant and wall-thickening lesions. Here, the features on EUS were outlined. We also outlined the current status of EUS-FNA for gallbladder lesions as there have been scattered reports of EUS-FNA in recent years.

Association between the non-HDL-cholesterol-to-HDL-cholesterol ratio and the risk of gallbladder polyp formation among men: a retrospective cohort study

Background

Dyslipidaemia and male sex are associated with gallbladder polyp (GBP) formation. However, the potential relation between the non-high-density lipoprotein-cholesterol-to-high-density lipoprotein-cholesterol (non-HDL-c/HDL-c) ratio and GBPs in men is unclear.

Methods

A total of 1866 eligible subjects were selected for this retrospective cohort study from Wuhan Union Hospital between April 1, 2013, and November 30, 2014. Clinical and laboratory data of subjects were collected. Patients with GBPs or cholecystectomy at baseline, with missing data for baseline lipid profiles, following abdominal ultrasonography or taking lipid-lowering drugs were excluded. The patients were divided into five groups based on their non-HDL-c/HDL-c ratios, and descriptive analyses of the baseline data were performed. A Cox proportional hazards model was applied to estimate the relationship between the non-HDL-c/HDL-c ratio and GBPs.

Results

After a median follow-up of 1 year, 7.34% (n = 137) of the subjects developed GBPs. Compared with subjects without GBPs, those who developed GBPs after follow-up had significantly higher triglyceride (TG) levels and non-HDL-c/HDL-c ratios. The prevalence of GBPs showed a linearity increment with age, peaked in the 30–39 years group, 40–49 years group and 50–59 years group, and then declined slightly. The results of univariate analysis showed that the non-HDL-c/HDL-c ratio (hazard ratio (HR) = 1.29, 95% confidence interval (CI), 1.05–1.60, P = 0.0159) was positively correlated with GBPs. In the fully adjusted Cox regression model, the HRs were 2.24 for quintile 2 (95% CI: 1.13–4.44, P = 0.0203), 1.50 for quintile 3 (95% CI: 0.73–3.10, P = 0.269), 2.52 for quintile 4 (95% CI: 1.26–5.01, P = 0.0087) and 2.13 for quintile 5 (95% CI: 1.04–4.37, P = 0.0397). No interaction was found among the subgroups.

Conclusions

A higher non-HDL-c/HDL-c ratio is independently related to a higher risk of GBP formation in Chinese men. Further research is needed to investigate whether this association exists in different regions and races.

Deep learning-based decision support system for the diagnosis of neoplastic gallbladder polyps on ultrasonography: Preliminary results

Ultrasonography (US) has been considered image of choice for gallbladder (GB) polyp, however, it had limitations in differentiating between nonneoplastic polyps and neoplastic polyps. We developed and investigated the usefulness of a deep learning-based decision support system (DL-DSS) for the differential diagnosis of GB polyps on US. We retrospectively collected 535 patients, and they were divided into the development dataset (n = 437) and test dataset (n = 98). The binary classification convolutional neural network model was developed by transfer learning. Using the test dataset, three radiologists with different experience levels retrospectively graded the possibility of a neoplastic polyp using a 5-point confidence scale. The reviewers were requested to re-evaluate their grades using the DL-DSS assistant. The areas under the curve (AUCs) of three reviewers were 0.94, 0.78, and 0.87. The DL-DSS alone showed an AUC of 0.92. With the DL-DSS assistant, the AUCs of the reviewer’s improved to 0.95, 0.91, and 0.91. Also, the specificity of the reviewers was improved (65.1–85.7 to 71.4–93.7). The intraclass correlation coefficient (ICC) improved from 0.87 to 0.93. In conclusion, DL-DSS could be used as an assistant tool to decrease the gap between reviewers and to reduce the false positive rate.

Clinical relevance of gallbladder polyps; is cholecystectomy always necessary?

BACKGROUND

Gallbladder polyps are common incidental findings during abdominal ultrasonography. Cholecystectomy is recommended for polyps equal or greater than 10 mm on ultrasound due to their malignant potential. However, the majority of lesions appear to be pseudopolyps with no malignant potential. Our aim was to determine the correlation between ultrasonographic findings and histopathological findings after cholecystectomy for gallbladder polyps in two institutions.

METHOD

A retrospective analysis was performed at two Dutch institutions of patients who underwent cholecystectomy. All cholecystectomies for suspected gallbladder polyps between January 2010 and August 2017 were included. Ultrasonographic and histopathological reports were analyzed.

RESULTS

A total of 108 patients underwent cholecystectomy for gallbladder polyps. At abdominal ultrasound sixty-five patients (60.2%) were diagnosed with multiple gallbladder polyps. The mean diameter of the polyps was 11 mm. On pathological examination after cholecystectomy, only three specimens harbored true polyps. No anomalies were found in 48 (44%) patients and 51 (47%) had cholesterolosis.

CONCLUSION

The prevalence of true gallbladder polyps was much lower in this study than reported in literature. After cholecystectomy for gallbladder polyps diagnosed by ultrasound, 97% of patients had non-neoplastic or not identifiable lesions in the gallbladder. These findings question the usefulness of current guidelines for management of suspected gallbladder polyps.

The accuracy of ultrasonography for diagnosis of gallbladder polyps

INTRODUCTION

Gallbladder polyps (GBPs) are gallbladder lesions which can progress to gallbladder malignancy. The incidence has been estimated as high as 12.1% of all cholecystectomy patients. Gallbladder malignancy typically presents late, and therefore carries a poor prognosis. By identifying potential GBPs early, it would be possible to treat polyps before they undergo malignant change. The current gold standard for GBP identification is with histological examination which is performed after cholecystectomy. This study sought to assess whether radiological imaging could reliably identify GBPs and therefore guide management.

METHODS

1000 consecutive patients already undergoing cholecystectomy were sampled from two UK hospitals. Patients who underwent ultrasonography and had histological analysis of their gallbladders were selected. Overall 905 patients were included in the study.

RESULTS

There were 12 histologically confirmed GBPs in the cohort (1.33%). US correctly detected 1 GBP, with a sensitivity of 8.3% (95% CI 0.2-38.5%) and specificity of 96.0% (95% CI 94.5-97.2%). The overall accuracy was 94.8 (95% CI 93.2-96.2%).

CONCLUSION

These data show that US is an ineffective tool for GBP identification. The lack of prior operator exposure, imprecise nature of US and possible obstruction of images from underlying gallstone disease delivered a high rate of false positives.

IMPLICATIONS FOR PRACTICE

Surgical or oncological decisions regarding GBPs should not be based upon US findings alone as this would lead to unnecessary interventions. MRI should be investigated as an alternative imaging modality for GBP identification, as its differentiation of soft tissues could guide surgical management.

Intraobserver and interobserver reliability in sonographic size measurements of gallbladder polyps

OBJECTIVES

To evaluate the intraobserver and interobserver reliability of gallbladder polyp measurements using transabdominal US and the factors that affect reliability.

METHODS

From November 2017 to February 2018, two radiologists measured the maximum diameter of 91 gallbladder polyps using transabdominal US. Intraobserver and interobserver agreement were determined using 95% Bland-Altman limits of agreement and intraclass correlation coefficients (ICCs). The effects of image settings, polyp location, and polyp size were evaluated by comparing ICCs using z tests.

RESULTS

The intraobserver agreement rates were 0.960 (95% confidence interval [CI], 0.939-0.973) for observer 1 and 0.962 (95% CI, 0.943-0.975) for observer 2. The ICCs between the two observers were 0.963 (95% CI, 0.926-0.979) for the first measurement and 0.973 (95% CI, 0.950-0.984) for the second measurement. The 95% limits of agreement on repeated measurements were 22.3-25.2% of the mean, and those between the two observers were 25.5-34.2% of the mean. ICCs for large polyps (≥ 5 mm) were significantly higher than those for small polyps (< 5 mm). There were no significant differences in the ICCs between image settings and polyp location.

CONCLUSIONS

Polyp size measurements using transabdominal US are highly repeatable and reproducible. Polyp size significantly affects the reliability of measurement. Diameter changes of approximately less than 25% may fall within the measurement error; this should be considered while interpreting the change in size during follow-up US, especially for small polyps.

KEY POINTS

• Gallbladder polyp size measurement using transabdominal US is highly repeatable and reproducible. • Diameter changes of approximately less than 25% should be interpreted carefully, especially in small polyps.

Computer-aided diagnosis of gallbladder polyps based on high resolution ultrasonography.Comput Methods Programs Biomed. 2020;185:105118. [PMID: 31671340 DOI: 10.1016/j.cmpb.2019.105118]

BACKGROUND AND OBJECTIVE

Gallbladder polyp is a common disease with an overall population prevalence between 4 and 7%. It can be classified as neoplastic and non-neoplastic lesions. Surgical treatment is necessary for neoplastic polyps. Due to its easy accessibility and nonradioactive, ultrasonography is the mostly used preoperative diagnosis tool for gallbladder polyps. However, human image analysis depends greatly on levels of experience, which results in many overtreatment cases and undertreatment cases in clinics.

METHODS

In this study, we proposed an ultrasound image segmentation algorithm, combined with principal components analysis (PCA) and AdaBoost algorithms to construct a computer-aided diagnosis system for the differentiate diagnosis of neoplastic and non-neoplastic gallbladder polyps.

RESULTS

The proposed segmentation method achieved a high accuracy of 95% for outlining the gallbladder region. The accuracy, sensitivity, specificity for the proposed computer-aided diagnosis system based on the segmented images are 87.54%, 86.52% and 89.40%, compared to 69.05%, 67.86% and 70.17% with convolutional neural network. The diagnosis result is also slightly higher than the human eyes of sonologists (86.22%, 85.19% and 89.18% as an average of four sonologists), while with a much faster diagnosis speed (0.02s vs 3s).

CONCLUSIONS

We proposed an efficient ultrasound image segmentation approach and a reliable system of automatic diagonals of neoplastic and non-neoplastic gallbladder polyps. The results show that the diagnosis accuracy is competitive to the expert sonologists while requires much less diagnosis time.

Neoplastic polyps in gallbladder: a retrospective study to determine risk factors and treatment strategy for gallbladder polyps

Background

Preoperative differentiation of malignant and premalignant gallbladder polyps (GBPs) from benign lesions is a key imperative to guide treatment decision-making. We aimed to characterize the various types of GBPs and sought to identify the risk factors for neoplastic polyps. Our findings may help optimize treatment strategy.

Methods

Retrospective analysis of 686 patients with post-cholecystectomy pathologically-proven GBPs between January 2003 and December 2016. The patients were classified into non-neoplastic polyp group, benign neoplastic polyp group, and adenoma canceration group. Clinical features, ultrasound findings, and results of laboratory investigations and histopathological examination were reviewed and compared between the groups.

Results

Out of 686 patients, 542 (79.0%) had non-neoplastic polyps, 134 (19.5%) had neoplastic polyps, and 10 (1.5%) had adenoma canceration. The mean age was 46.06±12.12 years; 383 (55.8%) patients were female. The median (25^th percentile, 75^th percentile) time between diagnosis and surgery in the cholesterol polyp group [24 (3.5, 60) months] was significantly longer than that in adenoma [12 (2, 60) months] and adenoma canceration [5 (0.475, 12) months] groups. The mean diameter was 1.14±0.61 cm (range, 0.5-8.4 cm). Three hundred twelve (45.5%) patients had solitary polyps and intralesional blood flow was observed in 41 (6.0%) patients. On univariate analysis, age >49.5 years, polyp size >1.15 cm, solitary polyp, intralesional blood flow, absence of symptoms, and lack of cholecystitis showed a significant association with adenoma. On multivariate analysis, polyp size (>1.15 cm), intralesional blood flow, and lack of cholecystitis were independent predictors of adenoma.

Conclusions

Polyp size >1.15 cm, intralesional blood flow, and lack of cholecystitis were predictors of neoplastic polyps. Malignant transformation of adenoma may occur over a relatively short time.

Risk factors of gallbladder polyps formation in East Asian population: A meta-analysis and systematic review

To perform Meta-analysis to identify risk factors associated with gallbladder polyps (GBP) formation in east Asian population. Three English electronic bibliographic databases includes PubMed, Embase and Medline, with reviewed researches from 1986 to 2017. All possible risk factors of GBP formation were recorded. Meta-analyses were performed by Review Manager Software. Pooled odds ratios (OR) or the mean difference (MD) were used to determine risk factors. Sixteen studies and 227021 people were recruited, including 17261 people with GBP and 209760 without GBP. For categorical variables evaluated by OR test., risk factors of GBP formation were male gender (OR, 1.63; 95%CI, 1.42-1.87) and positive HBsAg. GBP formation were not correlated with age <50 years old, hypertension, DM, BMI ≥ 25kg/m², smoking, drinking, HDL decrease, TC increase, TG increase, fatty liver and GBS. For continuous variables evaluated by MD test, risk factors of GBP formation were DBP (MD, 1.08; 95%CI, 0.15-2.02), mean BMI (MD,0.19; 95%CI,0.02-0.35), waist circumference (MD,1.780; 95%CI, 0.17,3.40), mean LDL (MD,0.89; 95%CI,0.03-1.75), mean HDL (MD,-1.87; 95%CI,-3.21 to -0.52). GBP formation were not correlated with mean age, SBP, mean TC, mean TG, ASL and ALT. In conclusion, risk factors of gallbladder polyp formation included male gender, higher BMI, higher waist circumference, higher DBP, higher LDL, lower HDL and positive HBsAg in east Asian population. GBP formation was not correlated with age, hypertension, DM, smoking, drinking, fatty liver, GBS, TC, TG, SBP, ASL and ALT. The mechanism of Dyslipidemias causing GBP needs deeper study in future.

Gallbladder polyps - a follow-up study after 11 years

Background

The aim of our study was to investigate the prevalence and natural long-term progression of gallbladder polyps in a random sample of the general population.

Methods

Four hundred and thirteen subjects (190 women, 223 men; aged 29–75 years) were studied first in 2002 and again eleven years later in 2013. All subjects were interviewed using a standardised questionnaire, anthropometric data were recorded, and an abdominal ultrasound scan was carried out.

Results

The prevalence of gallbladder polyps was 6.1% (115/1880) in the 2002 study and 12.1% (50/413) in the 2013 follow-up study. After eleven years, 36 subjects (8.7%, 36/413) had developed new polyps, thirteen subjects (48.1%, 13/27) no longer had gallbladder polyps, and 14 subjects (51.9%, 14/27) still had polyps. The number of polyps had increased in six of these subjects (43%, 6/14), decreased in a further six (43%, 6/14), and remained unchanged in two (14%, 2/14). The mean polyp size was 4.7 mm (± 2.2 mm, range 2–20 mm) in 2002 and 4.0 mm (± 1.9 mm, range 0.5–11 mm) at follow-up. A decrease in polyp size was noted in seven (50%) of the 14 subjects, an increase in size in five subjects (35.7%), and no change in two subjects (14.3%). The shape of the polyps had changed from pedunculated to sessile in two subjects (14.3%, 2/14) and from sessile to pedunculated in one subject (7.1%, 1/14).

Conclusions

In long-term follow-up, the prevalence of gallbladder polyps increased, with new lesions developing in 8.7% of the population. Polyps persisted in 51.9% of the subjects who had them in the original study and disappeared in the other 48.1%.

Correlation of dyslipidemias and gallbladder polyps-A large retrospective study among Chinese population

OBJECTIVE

Aim to explore the association of dyslipidemias with GBP prevalence, number and size in a large Chinese population in Beijing. Dyslipidemias include hypercholesterolemia, hypertriglyceridemia, increased low density lipoprotein (LDL) and decreased high density lipoproteins (HDL).

METHODS

Prevalence of GBP and its association with dyslipidemias were retrospectively investigated among subjects who underwent check-up at Health Screening Center of Xuanwu Hospital between January 2014 and December 2017.

RESULTS

This study enrolled 97117 participants. Prevalence of GBP was 7.3%. There were significant differences in increased LDL (595/7107 vs 6004/90010, P = 0.000) and increased cholesterol (TC) (403/7107 vs 4846/90010,P = 0.000) between GBP group and control group, but not in decreased HDL and increased triglyceride (TG). Logistic regression analysis showed that gender, age, BMI, SBP, DBP and LDL were independently associated with GBP. People with increases LDL had 1.488 times higher risk for GBP formation. Trend of dyslipidemias prevalence change according to age was similar with that of GBP. Increased LDL group had higher GBP prevalence rate (9.0% vs 7.2%, p = 0.000), multiple GBP proportion (2.9% vs 2.2%, p = 0.000) and large polyps with diameter ≥ 5 mm proportion (3.7% vs 2.6%,p = 0.000). Comparing with control group, there was higher proportion of large polyps in Increased TC group (3.2% vs 2.7%, p = 0.019) and decreased HDL group (3.0% vs 2.6%,p = 0.028). Increased TG group had not difference with its control group in GBP prevalence, number or size.

CONCLUSION

Dyslipidemias is associated with GBP formation. Dyslipidemias change according to age is consistent with GBP prevalence. Increased LDL was a more related risk factor rather than decreased HDL, increased TC or TG.

Ovo-lactovegetarian diet as a possible protective factor against gallbladder polyps in Taiwan: A cross-sectional study

Objective

Gallbladder polyps (GBPs) are an increasingly common incidental finding and 3% to 8% of GBPs become malignant. A poor prognosis is expected in patients with gallbladder cancer. No studies have considered the relationship between diet and the development of GBPs in the Taiwanese population. The objective of this study was to investigate whether a vegetarian diet protects against GBP development.

Materials and Methods

This cross-sectional study included 11,717 individuals who received a health checkup at Taipei Tzu Chi Hospital (New Taipei City, Taiwan) between October 2011 and October 2016. All individuals completed questionnaires that collected data about their characteristics, dietary patterns, and lifestyle. Physical examinations were conducted, and blood chemistry tests were performed. The presence of GBPs was determined using ultrasonography. We subsequently evaluated the association between diet and GBP prevalence using multivariate analysis.

Results

The prevalence of GBPs for the entire group was 8.3%. GBPs were significantly less common in the vegetarian groups (vegans 9.0%, ovo-lacto vegetarians 7.5%, and semi-vegetarians 7.2%) compared with the omnivore group (9.6%) (P = 0.002). Step-wise logistic regression revealed that an ovo-lacto vegetarian diet was a possible protective factor (odds ratio = 0.83, P = 0.015).

Conclusions

The study findings showed a strong negative association between an ovo-lacto vegetarian diet and GBP occurrence.

Strategy for discriminating cholesterol and premalignancy in polypoid lesions of the gallbladder: a single-centre, retrospective cohort study

BACKGROUND

The present study aimed to assess the risk factors of cholesterol and premalignancy in polypoid lesions of the gallbladder (PLGs) and to establish an appropriate treatment strategy.

METHODS

Data from patients who underwent cholecystectomy at the First Affiliated Hospital, School of Medicine, Zhejiang University, between January 2011 and July 2017, were collected retrospectively.

RESULTS

A total of 1561 patients were included in the present study. The cohort comprised of 636 (40.7%) males and 925 (59.3%) females, with a mean age of 49.5 (range 16-88) years; 65.6% (1024/1561) demonstrated cholesterol lesions in this cohort, among which cholesterol polyps accounted for 81.0%. Age younger than 50 years and multiple number of polyps were found to be independent predictive variables for cholesterol lesions (odds ratio (OR) 3.461, 95% confidence interval (CI) 2.058-5.820, P < 0.001 and OR 3.321, 95% CI 1.988-5.547, P < 0.001, respectively). The presence of polyp growth was associated with premalignancy (OR 5.366, 95% CI 1.466-19.637, P = 0.011), and the presence of clinical symptoms indicated benign non-cholesterol lesions (OR 0.368, 95% CI 0.153-0.885, P = 0.026).

CONCLUSION

In the case of patients ≥50 years old with single asymptomatic polyp, cholecystectomy was recommended if the polyp presented growth at a rate above 3-4 mm within 6 months. If not, trimonthly ultrasound follow up was recommended, and clinicians should carefully assess the risk factors for premalignancy in PLGs.

Metabolic status and lifestyle factors associated with gallbladder polyps: a covariance structure analysis

Background

Gallbladder Polyps (GBP) are highly prevalent in China; however, the etiology of GBP has not been clearly defined. This study explored the associations between lifestyle factors and GBP and whether it mediated by metabolic factors or not.

Methods

A total of 487 newly diagnosed GBP cases and 502 healthy controls were involved in this study. A questionnaire was used to investigate the socio-demographic characteristics and lifestyle factors. Food Intake Frequencies Questionnaire was used to obtain the food intake frequencies of seven food categories. Blood was tested for lipid profiles, fasting blood glucose and blood urine acid. A Covariance Structure Analysis was used in the analysis to explore the possible pathways between socio-demographic characteristics, lifestyle factors, metabolic factor and GBP.

Results

The Covariance Structure Analysis showed that a higher BMI and elevated triglyceride level mediated the association between age and GBP. Lifestyle factors (smoking and drinking) and higher intake frequencies of fatty food (meat and viscera) also linked to higher BMI and higher triglyceride level, respectively, which were associated with GBP.

Conclusion

In conclusion, age and lifestyle factors might be indirectly related with GBP through BMI and the triglyceride pathway.

Transabdominal ultrasound and endoscopic ultrasound for diagnosis of gallbladder polyps

BACKGROUND

Approximately 0.6% to 4% of cholecystectomies are performed because of gallbladder polyps. The decision to perform cholecystectomy is based on presence of gallbladder polyp(s) on transabdominal ultrasound (TAUS) or endoscopic ultrasound (EUS), or both. These polyps are currently considered for surgery if they grow more than 1 cm. However, non-neoplastic polyps (pseudo polyps) do not need surgery, even when they are larger than 1 cm. True polyps are neoplastic, either benign (adenomas) or (pre)malignant (dysplastic polyps/carcinomas). True polyps need surgery, especially if they are premalignant or malignant. There has been no systematic review and meta-analysis on the accuracy of TAUS and EUS in the diagnosis of gallbladder polyps, true gallbladder polyps, and (pre)malignant polyps.

OBJECTIVES

To summarise and compare the accuracy of transabdominal ultrasound (TAUS) and endoscopic ultrasound (EUS) for the detection of gallbladder polyps, for differentiating between true and pseudo gallbladder polyps, and for differentiating between dysplastic polyps/carcinomas and adenomas/pseudo polyps of the gallbladder in adults.

SEARCH METHODS

We searched the Cochrane Library, MEDLINE, Embase, Science Citation Index Expanded, and trial registrations (last date of search 09 July 2018). We had no restrictions regarding language, publication status, or prospective or retrospective nature of the studies.

SELECTION CRITERIA

Studies reporting on the diagnostic accuracy data (true positive, false positive, false negative and true negative) of the index test (TAUS or EUS or both) for detection of gallbladder polyps, differentiation between true and pseudo polyps, or differentiation between dysplastic polyps/carcinomas and adenomas/pseudo polyps. We only accepted histopathology after cholecystectomy as the reference standard, except for studies on diagnosis of gallbladder polyp. For the latter studies, we also accepted repeated imaging up to six months by TAUS or EUS as the reference standard.

DATA COLLECTION AND ANALYSIS

Two authors independently screened abstracts, selected studies for inclusion, and collected data from each study. The quality of the studies was evaluated using the QUADAS-2 tool. The bivariate random-effects model was used to obtain summary estimates of sensitivity and specificity, to compare diagnostic performance of the index tests, and to assess heterogeneity.

MAIN RESULTS

A total of 16 studies were included. All studies reported on TAUS and EUS as separate tests and not as a combination of tests. All studies were at high or unclear risk of bias, ten studies had high applicability concerns in participant selection (because of inappropriate participant exclusions) or reference standards (because of lack of follow-up for non-operated polyps), and three studies had unclear applicability concerns in participant selection (because of high prevalence of gallbladder polyps) or index tests (because of lack of details on ultrasound equipment and performance). A meta-analysis directly comparing results of TAUS and EUS in the same population could not be performed because only limited studies executed both tests in the same participants. Therefore, the results below were obtained only from indirect test comparisons. There was significant heterogeneity amongst all comparisons (target conditions) on TAUS and amongst studies on EUS for differentiating true and pseudo polyps.Detection of gallbladder polyps: Six studies (16,260 participants) used TAUS. We found no studies on EUS. The summary sensitivity and specificity of TAUS for the detection of gallbladder polyps was 0.84 (95% CI 0.59 to 0.95) and 0.96 (95% CI 0.92 to 0.98), respectively. In a cohort of 1000 people, with a 6.4% prevalence of gallbladder polyps, this would result in 37 overdiagnosed and seven missed gallbladder polyps.Differentiation between true polyp and pseudo gallbladder polyp: Six studies (1078 participants) used TAUS; the summary sensitivity was 0.68 (95% CI 0.44 to 0.85) and the summary specificity was 0.79 (95% CI 0.57 to 0.91). Three studies (209 participants) used EUS; the summary sensitivity was 0.85 (95% CI 0.46 to 0.97) and the summary specificity was 0.90 (95% CI 0.78 to 0.96). In a cohort of 1000 participants with gallbladder polyps, with 10% having true polyps, this would result in 189 overdiagnosed and 32 missed true polyps by TAUS, and 90 overdiagnosed and 15 missed true polyps by EUS. There was no evidence of a difference between the diagnostic accuracy of TAUS and EUS (relative sensitivity 1.06, P = 0.70, relative specificity 1.15, P = 0.12).Differentiation between dysplastic polyps/carcinomas and adenomas/pseudo polyps of the gallbladder: Four studies (1,009 participants) used TAUS; the summary sensitivity was 0.79 (95% CI 0.62 to 0.90) and the summary specificity was 0.89 (95% CI 0.68 to 0.97). Three studies (351 participants) used EUS; the summary sensitivity was 0.86 (95% CI 0.76 to 0.92) and the summary specificity was 0.92 (95% CI 0.85 to 0.95). In a cohort of 1000 participants with gallbladder polyps, with 5% having a dysplastic polyp/carcinoma, this would result in 105 overdiagnosed and 11 missed dysplastic polyps/carcinomas by TAUS and 76 overdiagnosed and seven missed dysplastic polyps/carcinomas by EUS. There was no evidence of a difference between the diagnostic accuracy of TAUS and EUS (log likelihood test P = 0.74).

AUTHORS' CONCLUSIONS

Although TAUS seems quite good at discriminating between gallbladder polyps and no polyps, it is less accurate in detecting whether the polyp is a true or pseudo polyp and dysplastic polyp/carcinoma or adenoma/pseudo polyp. In practice, this would lead to both unnecessary surgeries for pseudo polyps and missed cases of true polyps, dysplastic polyps, and carcinomas. There was insufficient evidence that EUS is better compared to TAUS in differentiating between true and pseudo polyps and between dysplastic polyps/carcinomas and adenomas/pseudo polyps. The conclusions are based on heterogeneous studies with unclear criteria for diagnosis of the target conditions and studies at high or unclear risk of bias. Therefore, results should be interpreted with caution. Further studies of high methodological quality, with clearly stated criteria for diagnosis of gallbladder polyps, true polyps, and dysplastic polyps/carcinomas are needed to accurately determine diagnostic accuracy of EUS and TAUS.

Current practices and future prospects for the management of gallbladder polyps: A topical review

A gallbladder polyp is an elevation of the gallbladder mucosa that protrudes into the gallbladder lumen. Gallbladder polyps have an estimated prevalence in adults of between 0.3%-12.3%. However, only 5% of polyps are considered to be "true" gallbladder polyps, meaning that they are malignant or have malignant potential. The main radiological modality used for diagnosing and surveilling gallbladder polyps is transabdominal ultrasonography. However, evidence shows that other modalities such as endoscopic ultrasound may improve diagnostic accuracy. These are discussed in turn during the course of this review. Current guidelines recommend cholecystectomy for gallbladder polyps sized 10 mm and greater, although this threshold is lowered when other risk factors are identified. The evidence behind this practice is relatively low quality. This review identifies current gaps in the available evidence and highlights the necessity for further research to enable better decision making regarding which patients should undergo cholecystectomy, and/or radiological follow-up.

Reasonable cholecystectomy of gallbladder polyp - 10 years of experience

BACKGROUND AND OBJECTIVE

Although the incidence of carcinoma is not high in gallbladder polyps, it is essential to diagnose gallbladder cancer at an early stage to achieve a good therapeutic outcome. Therefore, the aim of this study was to define the characteristics of gallbladder polyps to establish sound criteria for surgical indications.

METHODS

In the current study, data from 516 patients with gallbladder polyps who underwent cholecystectomy were reviewed to correlate clinical features with histopathologic findings and identify risk factors with receiver-operating characteristic curves (ROCs).

RESULTS

Among the 516 patients who underwent cholecystectomy, 24 patients (4.6%) had cancerous change. The cancer group was significantly older (65.5 years (median, range 35-85)) than the non-cancer group (42 years (median, range 23-82)) (p < 0.001). Among the cancer group, the preoperative polyp size on ultrasonography was significantly larger (14 mm (median, range 9-30)) than the polyps in the non-cancer group (10.4 mm (median, range 1.9-45)) (p < 0.001). Using the ROC curve and considering the sensitivity and specificity for predicting malignant polyps, 12 mm may be a reasonable cutoff for considering a malignant polyp.

CONCLUSIONS

Gallbladder polyps with 10-11 mm in asymptomatic young patients (less than 50 years old) have low risk of malignancy, and therefore, a careful "wait and see with follow up by using ultrasonography strategy" might be more appropriate than immediate cholecystectomy.

The gallbladder polypoid-lesions conundrum: moving forward with controversy by looking back

Gallbladder polypoid-lesions (GPs) are found in 5-10% of the general population. Although the majority of GPs are asymptomatic and benign in nature, some of them can develop into cancer, which carries a poor prognosis. Currently, the risk factors, natural history and classification of GPs remain unclear, differentiation of benign from malignant or premalignant GPs based on available diagnostic modalities and/or features of patients and GPs remain difficult, and there are still no evidence-based guidelines to dictate when and how GPs of varying sizes and subtypes should be managed. All of these facts have left GPs in uncertainty. Areas covered: A literature search was performed using the terms 'gallbladder polyps' AND 'polypoid lesion of gallbladder' in the PubMed database from January 2000 to September 2016. Original and review articles on almost all aspects of GPs in humans, especially diagnosis, treatment and surveillance, were reviewed and analyzed. Reference lists of reviews and original articles were also examined for relevant publications. Expert commentary: The present article summarizes almost all aspects of GPs, analyzes the controversies, and outlines our data and comments. It is the authors' purpose that this article be beneficial for scientific, accurate and appropriate management of GPs.

Gallbladder polypoid lesions >15mm as indicators of T1b gallbladder cancer risk

BACKGROUND AND STUDY AIMS

Gallbladder polyps (GBPs) are found in 5-7% of the adult population. However, it is very important to differentiate between benign and malignant polyps to establish an appropriate treatment. The present study aimed to determine the relevance of the 10-mm size criterion and attempted to determine the cut-off diameter of T1b tumours, which requires additional surgical intervention.

PATIENTS AND METHODS

Cases with GBPs were collected between January 2005 and January 2015. A total of 109 patients were enroled retrospectively. Information on age, sex, ultrasound findings, and blood laboratory tests was reviewed. The 10-mm criterion and T1b tumours were examined.

RESULTS

Sixty-nine females and 40 males were included in the study. Patient age was 45±10.7years (range 27-70years). The 10-mm cut-off sensitivity and specificity for predicting malignant polyps was 93.6% and 85.2%, respectively. Fifteen patients had malignant pathologic results, and one patient had GBP <10mm (intraepithelial, 8mm). Two patients had intraepithelial tumours of 12 and 13mm. Twelve malignant patients had T1b tumours with polyp sizes >15mm.

CONCLUSION

Gallbladder cancer may occur in polyps of <10mm. Larger size and older age were predictors of neoplastic GBPs. We suggest 15mm as the optimal cut-off point to predict T1b cancer.

Management and follow-up of gallbladder polyps : Joint guidelines between the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery - European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE)

Objectives

The management of incidentally detected gallbladder polyps on radiological examinations is contentious. The incidental radiological finding of a gallbladder polyp can therefore be problematic for the radiologist and the clinician who referred the patient for the radiological examination. To address this a joint guideline was created by the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery – European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE).

Methods

A targeted literature search was performed and consensus guidelines were created using a series of Delphi questionnaires and a seven-point Likert scale.

Results

A total of three Delphi rounds were performed. Consensus regarding which patients should have cholecystectomy, which patients should have ultrasound follow-up and the nature and duration of that follow-up was established. The full recommendations as well as a summary algorithm are provided.

Conclusions

These expert consensus recommendations can be used as guidance when a gallbladder polyp is encountered in clinical practice.

Key Points

• Management of gallbladder polyps is contentious

• Cholecystectomy is recommended for gallbladder polyps >10 mm

• Management of polyps <10 mm depends on patient and polyp characteristics

• Further research is required to determine optimal management of gallbladder polyps

Clinical Relationship between Cholestatic Disease and Pituitary-Dependent Hyperadrenocorticism in Dogs: A Retrospective Case Series

Background

A high prevalence of cholestatic disease, including gallbladder mucocele (GBM), has been reported in dogs with naturally occurring pituitary‐dependent hyperadrenocorticism (PDH).

Hypothesis/Objectives

Differences exist in the clinical features of dogs with PDH and concurrent cholestatic disease, and also is the management of these dogs with trilostane.

Animals

Sixty‐five client‐owned dogs with naturally occurring PDH.

Methods

This was a retrospective, observational case series. Each dog was treated with trilostane for at least 3 months before the study, and had a good clinical response, as determined by owners. Statistical comparisons of clinical signs, results of routine blood tests, basal and post‐ACTH cortisol concentration, and optimal trilostane dosage were made after dogs were separated into the following 3 groups by ultrasonographic imaging: normal on ultrasound (NOU) group, cholestasis group, and GBM group.

Results

The GBM group had more severe clinical signs and significantly different total serum cholesterol concentration and post‐ACTH stimulation cortisol concentration at the time of diagnosis. Dogs that weighed <6 kg had a significantly higher prevalence of cholestatic disease than did the other dogs (P = .003). The optimal trilostane dosages for the GBM and cholestasis groups were 2.5 and 1.5 times the dosage of the NOU group, respectively (P < .001).

Conclusions and Clinical Importance

Gallbladder disease associated with cholestatic disease is correlated with PDH in dogs, in both its clinical features and drug management. These findings may be associated with hypercholesterolemia, unidentified genetic factors, and the hydrophobic nature of trilostane.

Prevalence and Risk Factors of Gallbladder Polypoid Lesions in a Healthy Population

PURPOSE

To determine the prevalence of and investigate the risk factors for gallbladder (GB) polypoid lesions in a healthy population.

MATERIALS AND METHODS

A total of 23827 subjects who underwent abdominal ultrasonography in conjunction with health screening examinations were retrospectively analyzed. The prevalence of risk factors for GB polypoid lesions were evaluated. In addition, risk factors according to the number of polypoid lesions and the presence of stones with polypoid lesions were investigated. To analyze these risk factors, a control group was established with a 1:2 ratio matched for age and sex.

RESULTS

The prevalence of GB polypoid lesions was identified as 9.96%. On multivariate analysis, chronic hepatitis B infection (CHB) and the presence of metabolic syndrome (MS) were risk factors for GB polypoid lesions. CHB and MS were also significant independent risk factors for multiple GB polypoid lesions when compared with solitary GB polypoid lesions. In addition, gastric Helicobacter pylori infection and MS were significant risk factors for GB polypoid lesions with stones when compared with GB polypoid lesions without stones.

CONCLUSION

The prevalence of GB polypoid lesions in a healthy Korean population was 9.96%. Patients with CHB and MS need to be carefully examined for such lesions.

Visceral Obesity Is Associated with Gallbladder Polyps

Background/Aims

Gallbladder polyps (GBP) are a common clinical finding and may possess malignant potential. We conducted this study to determine whether visceral obesity is a risk factor for GBP.

Methods

We retrospectively reviewed records of subjects who received both ultrasonography and computed tomography with measurements of the areas of visceral adipose tissue and total adipose tissue (TAT) on the same day as health checkups.

Results

Ninety-three of 1,615 subjects (5.8%) had GBP and were compared with 186 age- and sex-matched controls. VAT (odds ratio [OR], 2.941; 95% confidence interval [CI], 1.325 to 6.529; p=0.008 for the highest quartile vs the lowest quartile) and TAT (OR, 3.568; 95% CI, 1.625 to 7.833; p=0.002 for the highest quartile vs the lowest quartile) were independent risk factors together with hypertension (OR, 2.512; 95% CI, 1.381 to 4.569; p=0.003), diabetes mellitus (OR, 2.942; 95% CI, 1.061 to 8.158; p=0.038), hepatitis B virus positivity (OR, 3.548; 95% CI, 1.295 to 9.716; p=0.014), and a higher level of total cholesterol (OR, 2.232; 95% CI, 1.043 to 4.778; p=0.039 for <200 mg/dL vs ≥240 mg/dL). Body mass index and waist circumference were not meaningful variables.

Conclusions

Visceral obesity measured by VAT and TAT was associated with GBP irrespective of body mass index or waist circumference.

Evidence based management of polyps of the gall bladder: A systematic review of the risk factors of malignancy

BACKGROUND

There are no evidence-based guidelines to dictate when Gallbladder Polyps (GBPs) of varying sizes should be resected.

AIM

To identify factors that accurately predict malignant disease in GBP; to provide an evidence-based algorithm for management.

METHODS

A systematic review following PRISMA guidelines was performed using terms "gallbladder polyps" AND "polypoid lesion of gallbladder", from January 1993 and September 2013. Inclusion criteria required histopathological report or follow-up of 2 years. RTI-IB tool was used for quality analysis. Correlation with GBP size and malignant potential was analysed using Euclidean distance; a logistics mixed effects model was used for assessing independent risk factors for malignancy.

RESULTS

Fifty-three articles were included in review. Data from 21 studies was pooled for analysis. Optimum size cut-off for resection of GBPs was 10 mm. Probability of malignancy is approximately zero at size <4.15 mm. Patient age >50 years, sessile and single polyps were independent risk factors for malignancy. For polyps sized 4 mm-10 mm, a risk assessment model was formulated.

CONCLUSIONS

This review and analysis has provided an evidence-based algorithm for the management of GBPs. Longitudinal studies are needed to better understand the behaviour of polyps <10 mm, that are not at a high risk of malignancy, but may change over time.

Association of Gallbladder Polyp and Stroke: A Nationwide, Population-Based Study

Gallbladder polyp (GP) and stroke share several metabolic disorders as risk factors. We assessed the association between GP and subsequent stroke risk. From 2000 to 2011, patients with GP aged >20 years were identified from the Longitudinal Health Insurance Database 2000. Of the 15,975 examined patients, 12,780 and 3195 were categorized into the non-GP and GP cohorts, respectively. The relative risks of stroke were estimated using the Cox proportional hazard model after adjusting for age, sex, and comorbidities. The overall incidence of stroke was higher in the GP cohort than in the non-GP cohort (6.66 vs 5.20/1000 person-yr), with an incidence rate ratio (IRR) of 1.28 (95% confidence interval [CI] = 1.15-1.42). The risk of stroke was 1.32-fold (95% CI = 1.06-1.63) in patients with GP compared with patients without GP after adjusting for age, sex, income level, urbanization level, occupation and comorbidities of gallstone, alcohol-related illness, diabetes, hyperlipidemia, hypertension, obesity, COPD, coronary heart disease, and asthma. Furthermore, the stroke risk was higher among elderly patients (with 1-yr intervals; adjusted HR [aHR] = 1.06, 95% CI = 1.05-1.07), the male sex (aHR = 1.62, 95% CI = 1.35-1.96), lower income level (aHR = 1.37, 95% CI = 1.02-1.85 for level I; aHR = 1.62, 95% CI = 1.25-2.10 for level II), living in second urbanized areas (aHR = 1.28, 95% CI = 1.00-1.63), alcohol-related illness (aHR = 1.56, 95% CI = 1.07-2.28), diabetes (aHR = 1.78, 95% CI = 1.41-2.24), and hypertension (aHR = 2.74, 95% CI = 2.19-3.42). GP is associated with stroke; however, GP may be less influential than other risk factors are, such as male sex, lower income level, alcohol-related illness, diabetes, and hypertension, on stroke development. Additional studies are required to clarify whether GP is a risk factor for or an epiphenomenon of stroke development.